Dentifrice product



Patented Nov. 3, 1936 PATENT- OFFICE nsu'rrrmcr: rnonuc'r Jean Ripert,Paris, France, assignor. to-Thibaud, Gibbs 8; Cie., Paris, France,arcorporation of France No Drawing.

Application July 12'. 1934, Serial No. 734,797. In France January 9,1934 5 Claims. (01. 167-93) It is known that the abrasive substancescurrently employed in dentifrices are generally in crystalline oramorphous form divided into a plurality of fine particles having sharpangles 6 and many asperitiesvisible under the microscope.

Amongst the usual abrasives are calcium carbonate, precipitated chalk,powdered pumice stone, sodium sulphate, calcium phosphate, magnesiumcarbonate, zeolite, alum, cream of tartar,

l coral powder, talc, kaolin, sugar, milk sugar, potassium bitartrate,powdered cuttle fish bone, finely powdered sodium chloride,, infusorialearths (kieselguhr), zinc oxide, magnesium phosphate, barium carbonate,.calcium stearates of 15 magnesium or barium, calcium oxylate, glasssilk,

potassium chlorate, hydrated. or colloidal alumina, colloidal silica,etc.

Now, it has been found that these various abrasives generally have ahardness superior or equal to that of the enamel, and greater than thatof ivory, and also greater than that of the cement, such as exists atthe neck of the tooth.

Consequently, they show under the action of the brush seriousdisadvantages; on the one hand they produce by wear the erosion of theneck of the tooth which contributes to shrinking away of the gums fromthe tooth and renders them very sensitive or even painful, on the otherhand, instead of producing polishing of the tooth they produce in factthe reverse 'eifect by wear either 'of the prisms of the enamel or ofthe interprismatic substance. It may be remarked that there is neverwear of the two at the same time which explains why the unpolishingaction shows 35 itself by the production of a granular surface.

Teeth brought into this state show a quite particular susceptibility tocaries; which may be explained by the retaining on the surface of thetooth which hasbecome rugged of scraps of 40 food, by the action ofacids resulting from the decomposition of the scraps'and by the depositof tartar.

In order to obviate these serious disadvantages of the abrasivescurrently employed it has alreadybeen proposed to employ in dentifricesas abrasives, flexible materials such as silica. or bentonite, in theform of colloidal gel (which bentonite is known as producing a favorable-detergent colloidal gel by addition of water), cel- 50 lulose and itsesters,in the form of pulp and even paper in the form of paste. In factthese abrasives are too soft to produce the efficacious cleaning actionwhich the teeth require. They act in fact upon the surface of the teethlike a 56 true washing cloth", no more, but they cannot after havingremoved the film exercise a true polishing action on the enamel.

The present invention has for its object. an improvement applied to theconstitution of dentifrice products with the object of eliminat- 5 ingall these disadvantages and of permitting these products to have anefficacious polishing action leading to the production of a uniformlytrue surface while avoiding the excessive wear which is shown by thephenomena known as errosion abrasion etc.

For this purpose the invention employs as polishing. bodies substanceshaving a hardness equal to that 'of the cement but which wear morerapidly than the body to be polished. In using such substances the sharpangles of the polishing particles, for example the edges of a cube,

that natural or industrial silicates, the'degree of hardness of which,measured on Mohs scale lies-between 2 and 3, satisfy all theseconditions. In fact these substances while possessing a hardnesssubstantially equal to that of the cement, wear in contact with thislatter instead of wearing it, the sharp angles of their particlesblunting themselves from the beginning of the cleaning action. Myexperiments have shown that this result is due to the lamellarcrystalline structure of mica and the natural silicates constitutingmica. powder, even one which passes through a .sieve of 300 meshes,presents a lamellar structure. Furthermore, it is important to observethat the fiat particles always offer a tendency to present their flatsurfaces and not their sharp edges to the surfaces of the materials withwhich they come in contact. When, for instance, a quantity of micapowder is suspended in water or in glycerine, microscopic observationsshow that only the fiat surfaces are seen and not the sharp edges. 1Accordingly, mica particles arrange themselves parallel to the surfaceof a plane on which the mica is rubbed in such a manner that Itis to benoted that a mica 40 I not contatt with the sharp edges of theparticles. I have found, for example, that it is possible to rub asurface having a hardness far below 2.5

with mica powder having a hardness of 2.5, without producing anystriations thereon, but on the contrary, the surface so rubbed waspolished to a remarkable degree and had an appearance similar to thatwhich would be obtained by polishing with a chamois skin or othermaterial of very slight hardness. I have found that mica and silicatesentering into the constitution of mica have properties which make suchmaterial particularly suitable for cleansing teeth.

Amongst the natural silicates envisaged by the invention it isconvenient particularly to mention mica; the different varieties of micahaving a degree of hardness of the order of that indicated above.

In fact the hardness of the different micas evaluated by means of Mohsscale is as follows:-

Muscovite 2 to 2.5

Paragonite 2.5 to 4 Lepidolite 2.5 to 4 Zinnwaldite 2.5 to 3.5

Biotite 2.5 to 3 Phlogopite 2.5 to 3 Amongst these micas those which arethe easiest to procure commercially are those of which the hardness liesbetween 2.5 and 3.

The mica is used in the form of fine powder obtained by pulverizing andpassing through sieves either mica in sheets or in scraps. This powdermay be incorporated in a paste orin a dentifrice soap made according tothe usual formulae as will be indicated by the examples cited below. Onemay also use the mica powder as the principal ingredient of a dentifricepowder mixing with this powder other suitable substances such as a tastecorrector, perfume, colour etc.

Instead of using natural powdered mica one may use, under the naturallamellar crystalline forms which they show in the natural state, thesilicates entering into the composition of micas,

and which are notably the double silicate of aluminium and potassium(muscovite), the double silicate of aluminium and sodium (paragonite)the triple silicate of aluminium, potassium and lithium (lepidolite) thedouble silicate of iron and lithium (zinnwaldite), the triple silicateof iron, magnesium and potassium (biotite), phlogopite or potassium andmagnesium silicate combined with the double fluoride of potassium andmagnesium, lepidomelane, of composition analogous to biotite butcontaining a large percentage of iron in the ferric form, roscoelite,analogous to muscovite but with about 30% of vanadium oxide.

The invention can be carried into effect according to the non-limitingexamples which follow:

' Example 1.With '70 parts of a saponaceous paste made by emulsifying 5parts of soap, parts of glycerine, 54 parts of water, by means of 1 partof gum tragacanth there are incorporated 30 parts of finely ground mica.

Example 2.-'To 12 parts of a mucilage of gum tragacanth formed intopaste, 8 parts of glycerine are added. In this basis 2 parts of finelypulverized mica is incorporated. The consistency of the final productdepends upon that of the mucilage of gum traga'canth employed and thequantity of mica incorporated. There is thus obtained a non-latheringtooth paste.

Example 3.--A solution of giycerine and gelatine is prepared with 7.5parts of white gelatine, 120 parts of distilled water, 210 parts ofglycerine. To 120 parts of this mixture there are incorporated 36 partsof finely powdered mica. If it is desired to render this paste latheringto the mass is added '7 .5 parts of powdered soap.

Example 4.-To a basis for dentrifrice soaps in cakes prepared in theusual manner there is incorporated a powder of mica or silicatesconsti-- tuting the natural mica as filling materials in a proportion of20 to 25% for example.

Example 5.-Powdered mica or silicates of the P type indicated constitutethe basis of a dentifrice powder to which other suitable products may beadded.

In all the examples above the proportions may vary according to the endsought. Likewise other products such as antiseptics, bactericidalagents, astringents etc. may be added. The addition of perfume andcolouring material is naturally permissible.

I claim: I

1. A dentifrice preparation having as a polishing constituent finelypowdered silicates constituting the natural micas in their naturallamellar crystalline form and having a hardness not greater than about3.

2. A dentifrice preparation having as a polishing constituent finelypowdered silicates constituting the natural micas, which have a naturallamellar crystalline structure.

3. A dentifrice preparation having as a polishing constituent finely'powdered silicates consti-

